ubuntu-cve-2021-20206
Vulnerability from osv_ubuntu
Published
2021-03-26 22:15
Modified
2026-05-20 14:53
Summary
Details

An improper limitation of path name flaw was found in containernetworking/cni in versions before 0.8.1. When specifying the plugin to load in the 'type' field in the network configuration, it is possible to use special elements such as "../" separators to reference binaries elsewhere on the system. This flaw allows an attacker to execute other existing binaries other than the cni plugins/types, such as 'reboot'. The highest threat from this vulnerability is to confidentiality, integrity, as well as system availability.

Severity
7.2 (High)
CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:H
N/A (UNKNOWN)
medium
References
To clipboard 

{
  "affected": [
    {
      "ecosystem_specific": {
        "binaries": [
          {
            "binary_name": "golang-github-appc-cni-dev",
            "binary_version": "0.3.0+dfsg-1"
          }
        ]
      },
      "package": {
        "ecosystem": "Ubuntu:18.04:LTS",
        "name": "golang-github-appc-cni",
        "purl": "pkg:deb/ubuntu/golang-github-appc-cni@0.3.0+dfsg-1?arch=source\u0026distro=bionic"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "0.3.0+dfsg-1"
      ]
    },
    {
      "ecosystem_specific": {
        "binaries": [
          {
            "binary_name": "golang-github-appc-cni-dev",
            "binary_version": "0.7.1-2"
          }
        ]
      },
      "package": {
        "ecosystem": "Ubuntu:20.04:LTS",
        "name": "golang-github-appc-cni",
        "purl": "pkg:deb/ubuntu/golang-github-appc-cni@0.7.1-2?arch=source\u0026distro=focal"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "0.4.0+dfsg-1",
        "0.7.1-2"
      ]
    },
    {
      "ecosystem_specific": {
        "binaries": [
          {
            "binary_name": "golang-github-appc-cni-dev",
            "binary_version": "1.0.1-3"
          }
        ]
      },
      "package": {
        "ecosystem": "Ubuntu:22.04:LTS",
        "name": "golang-github-appc-cni",
        "purl": "pkg:deb/ubuntu/golang-github-appc-cni@1.0.1-3?arch=source\u0026distro=jammy"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "0.8.1-1",
        "1.0.1-3"
      ]
    },
    {
      "ecosystem_specific": {
        "binaries": [
          {
            "binary_name": "golang-github-appc-cni-dev",
            "binary_version": "1.1.2-1"
          }
        ]
      },
      "package": {
        "ecosystem": "Ubuntu:24.04:LTS",
        "name": "golang-github-appc-cni",
        "purl": "pkg:deb/ubuntu/golang-github-appc-cni@1.1.2-1?arch=source\u0026distro=noble"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "1.1.2-1"
      ]
    },
    {
      "ecosystem_specific": {
        "binaries": [
          {
            "binary_name": "golang-github-appc-cni-dev",
            "binary_version": "1.1.2-1"
          }
        ]
      },
      "package": {
        "ecosystem": "Ubuntu:25.10",
        "name": "golang-github-appc-cni",
        "purl": "pkg:deb/ubuntu/golang-github-appc-cni@1.1.2-1?arch=source\u0026distro=questing"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "1.1.2-1"
      ]
    },
    {
      "ecosystem_specific": {
        "binaries": [
          {
            "binary_name": "golang-github-appc-cni-dev",
            "binary_version": "1.3.0-1"
          }
        ]
      },
      "package": {
        "ecosystem": "Ubuntu:26.04:LTS",
        "name": "golang-github-appc-cni",
        "purl": "pkg:deb/ubuntu/golang-github-appc-cni@1.3.0-1?arch=source\u0026distro=resolute"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "1.1.2-1",
        "1.3.0-1"
      ]
    }
  ],
  "aliases": [],
  "details": "An improper limitation of path name flaw was found in containernetworking/cni in versions before 0.8.1. When specifying the plugin to load in the \u0027type\u0027 field in the network configuration, it is possible to use special elements such as \"../\" separators to reference binaries elsewhere on the system. This flaw allows an attacker to execute other existing binaries other than the cni plugins/types, such as \u0027reboot\u0027. The highest threat from this vulnerability is to confidentiality, integrity, as well as system availability.",
  "id": "UBUNTU-CVE-2021-20206",
  "modified": "2026-05-20T14:53:03Z",
  "published": "2021-03-26T22:15:00Z",
  "references": [
    {
      "type": "REPORT",
      "url": "https://ubuntu.com/security/CVE-2021-20206"
    },
    {
      "type": "REPORT",
      "url": "https://github.com/containernetworking/cni/pull/808"
    },
    {
      "type": "REPORT",
      "url": "https://bugzilla.redhat.com/show_bug.cgi?id=1919391"
    },
    {
      "type": "REPORT",
      "url": "https://www.cve.org/CVERecord?id=CVE-2021-20206"
    }
  ],
  "related": [],
  "schema_version": "1.7.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:H",
      "type": "CVSS_V3"
    },
    {
      "score": "medium",
      "type": "Ubuntu"
    }
  ],
  "upstream": [
    "CVE-2021-20206"
  ]
}



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